{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "10239edf86f137ce4c39b62ea9575e8053c549a0"
            },
            {
              "fixed": "1113b674307ffddd402524bd1fd9d7d5629b705b"
            },
            {
              "fixed": "2e77947bbf6c166e76c038663832d0914418f761"
            },
            {
              "fixed": "0898c6f9fa9ce2632ae88bd0f34a878ccc6335af"
            },
            {
              "fixed": "eb56a495f59baf6cad5ed80e3ffb9078098b1346"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "3.14.0"
            },
            {
              "fixed": "6.12.111"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "fixed": "6.18.53"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "7.2.7"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98011.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: hhf: clamp quantum in change and init paths\n\nhhf_change() accepts any quantum from userspace, including 1. With a\ncrafted size table qdisc_pkt_len reaches ~2 GiB, so quantum=1 makes\nthe deficit-refill loop spin ~2^31 times under the qdisc lock\n(a soft lockup / denial of service).\n\nAdd max(256U, ...) in hhf_change() matching fq_codel_change(). Clamp\nhhf_init() to [256, 1\u003c\u003c20] matching the siblings, and remove the old\nfallback that only set quantum=256 on overflow.\n\nConditions to recreate the bug:\n  CONFIG_NET_SCH_HHF=y. Requires CAP_NET_ADMIN (namespace-local via\n  unshare -Urn suffices).\n\n  tc qdisc add dev dummy0 root hhf\n  tc qdisc change dev dummy0 root hhf quantum 1 stab data 32768 size_log 15 cell_log 0",
  "id": "CVE-2026-98011",
  "modified": "2026-09-27T03:30:44.298339729Z",
  "published": "2026-09-25T10:23:35.338Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/0898c6f9fa9ce2632ae88bd0f34a878ccc6335af"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/1113b674307ffddd402524bd1fd9d7d5629b705b"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/2e77947bbf6c166e76c038663832d0914418f761"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/eb56a495f59baf6cad5ed80e3ffb9078098b1346"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98011.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-98011"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.9.0",
  "summary": "net/sched: hhf: clamp quantum in change and init paths"
}